Please reference to Taiwanese patent no. TWM266131, the conventional vise device (or workpiece clamping device) may comprise a base, a fixing jaw, and a plurality of movable jaw. A sliding groove is arranged at a center of the base. A sliding track is arranged at each side of the sliding groove. The fixing jaw is bridged on the two sliding tracks of the base. One end of the fixing jaw is a clamping surface and a first sliding block is arranged under the fixing jaw and screwed with each other with a bolt. The first sliding block is received in the sliding groove of the base so that the fixing jaw is fixed on the base. The movable jaw includes a first inclined block and a second inclined block. One end is of the first inclined block has a first inclined surface and the other end thereof has a clamping surface. A second sliding block is arranged under the first inclined block and screwed with each other a bolt. The second sliding block is received in the sliding groove of the base. One end of the second inclined block has a second inclined surface abutted against the first inclined surface and the other end thereof is a clamping surface. A third sliding block is arranged under the second inclined block and screwed with each other with a blot. When the vise device is operating, a workpiece may be arranged between the fixing jaw and the second inclined block so that the first inclined surface and the second inclined surface may be pushed each other to clamp the workpiece.
However, when the bolt of the second inclined block is screwed out (the workpiece is disassembled), the second inclined block may be stopped between the workpiece and the first inclined surface of the first sliding block due to the structure of the inclined surface to result in the finished workpiece being not able to disassemble from the vise device normally. Besides, before the second inclined block is not clamping the workpiece, it is easy to slide downward due to the weight. The gap size between the fixing jaw and the second inclined block may become smaller so that one hand of the operator must hold the second inclined block and the other hand thereof put the workpiece to a clamping position. It makes the operating process more complicated.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve this problem.